Ventilation is the physiologic process which supplies oxygen to the body and removes carbon dioxide, a gaseous waste product. Normally, ventilation is provided from the cyclic flow of gas into and out of the lungs. The flow results from the contraction and relaxation of the diaphragm. Many surgical and critical care patients are unable to ventilate adequately, and ventilation must be provided mechanically using a mechanical ventilator and a single lumen endotracheal tube. An endotracheal tube (ETT) typically is comprised of a lumen or tube that is open at both ends, and has a comfort cuff or balloon positioned at one end. An ETT is positioned in the mid trachea whereby it acts as a conduit for gas from the ventilator to the lungs.
Patients who are critically ill or who have undergone surgical procedures require mechanical ventilation to sustain life. Patients that require mechanical ventilation for prolonged periods of time often develop a potentially fatal condition called ventilator-associated pneumonia or VAP. VAP is caused by bacteria build up in the moist environment on the ventilation tubing apparatus and infects the patient's lungs.
VAP is a major threat to the recovery of patients receiving mechanical ventilation, and is the most lethal infection in mechanically ventilated patients. VAP was the most frequent nosocomial infection aquired in ICUs in Europe, accounting for 45 percent of all infections. J L Vincent, D J Bihari, P M Suter, H A Bruining, J White, M H Nicolas-Chanoin, M Wolff, R C Spencer, M Hemmer: The prevalence of nosocomial infection in intensive care units in Europe. Results of the European Prevalence of Infection in Intensive Care (EPIC) Study. J Am Med Assoc 1995, 278: 639-644. The early and accurate diagnosis of VAP is difficult, but because of the increasing prevalence of multi-resistant pathogens in many ICUs; it constitutes an urgent challenge. It is especially difficult to distinguish VAP from other causes of fever and infection. A fatal outcome is frequently observed in patients who are mechanically ventilated for more than 48 hours. Several investigators have hypothesized that VAP has a direct causal influence on mortality. J Y Fagon, J Chastre, A J Hance, P Montravers, A Novara, C Gibert: Nosocomial pneumonia in ventilated patients: a cohort study evaluating attributable mortality and hospital stay, Am J Med 1993, 94: 281-288.
VAP can make a patient ill for a very long time or even cause death in critically ill patients, especially in infants and the elderly. In order to prevent or lessen the threat of VAP, health care professionals repeatedly re-intubate patients that require ventilation over long periods of time. Accordingly, there is a need in the art for an endotracheal tube apparatus designed for prolonged ventilation, which aids in preventing the VAP. Embodiments of the invention described herein utilize a unique tube in tube endotracheal tube design that provides for ventilation and suctioning. The tube in tube arrangement also allows for replacement of the ventilation tube of the endotracheal tube to prevent bacterial build up that can cause VAP.
Furthermore, the shape of the distal ends of current tracheal tubes can cause extensive damage to tracheal during intubation. A less intrusive tubal design would be desirous to reduce the injury and damage caused by the process of intubing a patient.